Moved Product Properties out of creating_products and into its own user guide.
Intro to orders on user guide
Cleaned up the Products user guide intro
Prototype User Guide
Very, very long entering orders guide.
Editing orders user guide
Processing orders user guide
Returning orders user guide
Fixed slight routing issue with user/inventory guides
Payments Intro for user guides
Configuration Intro for user guide
General Settings User Configuration Guide
Mail Methods guide; added an Introduction section to remaining Configuration user guides.
Rewrote much of the creating products user guide, with several new screenshots
New screenshot for user guide products intro
New screenshots & fixed link on payment_states
Updated "Total" description; removed TODO on searching_orders guide
Some rewrites and new screenshots to payment_methods user guide
Configuring Image Settings User Guide
Taxation configuration user guide; a few tweaks to the Images configuration guide.